--- name: "nfsd" section: "8" platform: "macos" package: "NFS" version: "343.100.5" release: "macOS 26.5" platforms: ["linux", "freebsd", "openbsd", "macos"] url: "https://new.carta.tech/nfsd" --- # nfsd(8) NFS server daemon ## NAME **nfsd** – NFS server daemon ## SYNOPSIS **nfsd** \[**command**\] **nfsd** \[**-F** *exports\_file*\] **checkexports** **nfsd** \[**-NRrtuv**\] \[**-F** *exports\_file*\] \[**-n** *num\_servers*\] \[**-p** *nfsport*\] \[**-P** *mountport*\] \[**command**\] ## DESCRIPTION **nfsd** runs on an NFS server machine to service NFS and MOUNT protocol requests from NFS client machines. In order for a machine to act as an NFS server an NFS exports file, */etc/exports*, must exist and the **nfsd** service must be enabled. **nfsd** listens for NFS service requests at the port indicated in the NFS server specification (2049) and the mountd thread listens for MOUNT service requests at an available port registered with [portmap(8)](/portmap/8.md). For more information on the NFS and MOUNT protocols see RFC1094 and The **nfsd** daemon is a multi-threaded process that includes a number of threads processing NFS requests, a thread to accept new socket connections and a thread that processes NFS MOUNT protocol requests. When **nfsd** is started, it loads the export host addresses and options into the kernel using the [nfssvc(2)](/nfssvc/2.md) system call. After changing the list of exports (either directly or indirectly via a change in netgroup membership), a hangup signal should be sent to the daemon to get it to reload the export information. This can be accomplished with the **update** command described below. Any errors encountered while processing the export entries will be logged via [syslog(3)](/syslog/3.md). **nfsd** is normally launched by launchd(8); however, the **nfsd** command may also be used to manipulate the service using the following commands: - **enable** Enables the **nfsd** service. - **disable** Disables the **nfsd** service. - **start** Starts the **nfsd** service. Note: if the service is disabled it will not be restarted on reboot. Use the **enable** command to make the change permanent. - **stop** Stops the **nfsd** service. Note: if the service is enabled it will be restarted on reboot. Use the **disable** command to make the change permanent. - **restart** Restarts the **nfsd** service (by stopping the service - it will restart automatically if the */etc/exports* file exists). - **update** Sends a SIGHUP to the running **nfsd** daemon to cause it to update its configuration. - **status** Displays whether the **nfsd** service is enabled and whether the **nfsd** daemon is currently running. - **checkexports** Checks the exports file and reports any errors (to stderr). Note that this can be useful to verify the validity of an alternate exports file (using the **-F** option below) prior to putting the changes in place and updating **nfsd**. - **verbose** **\[up\|down\]+** Sends USR1 and/or USR2 signal(s) to the running **nfsd** daemon to cause it to increase and/or decrease its logging level. (See below for details about **nfsd**'s logging). Logging is performed via [syslog(3)](/syslog/3.md) using the LOG\_DAEMON facility. By default, only messages up to priority LOG\_WARNING are logged. Setting the verbose level to one will add LOG\_NOTICE messages which includes logging failed mount attempts. A verbose level of two will increase the log level to LOG\_INFO which includes logging successful mount attempts. A log level of three or more will add LOG\_DEBUG messages and cause increasing amounts of debug information to be logged. The debug information exposes lots of information about **nfsd**'s inner workings which is typically only useful to developers. Note: the syslog(8) configuration may need to be adjusted in order to see the increased verbosity. The **nfsd** utility exits 0 on success, and \>0 if an error occurs. When given the **status** command, it exits 0 if the service is enabled, and 1 if the service is disabled. The following is a list of command line options that are available. However, since **nfsd** is normally started by launchd(8), configuration of these options should be controlled using the equivalent settings in the NFS configuration file (see [nfs.conf(5)](/nfs.conf/5.md)). - **-F** *exports\_file* The *exports\_file* argument specifies an alternate location for the exports file (useful with the **checkexports** command). - **-N** Allow non-root mount requests to be served. This should only be specified if there are clients that require it. - **-P** *#* Specifies which port to use for the MOUNT service. - **-R** Allow mount RPCs requests for regular files to be served. Although this seems to violate the mount protocol specification, some diskless workstations do mount requests for their swapfiles and expect them to be regular files. Since a regular file cannot be specified in */etc/exports*, the **-alldirs** option will need to be used on the export in which the swap files reside. - **-n** *#* Specifies how many NFS server threads to create. - **-p** *#* Specifies which port to use for the NFS service (instead of the default of 2049). - **-r** Register the NFS service with [portmap(8)](/portmap/8.md). This option can be used to re-register the NFS services if the portmap server is restarted. This option is equivalent to the **update** command. - **-t** Serve TCP NFS clients. Note: only TCP will be used if no other options are specified. - **-u** Serve UDP NFS clients. Note: only UDP will be used if no other options are specified. - **-v** Increase **nfsd**'s logging level by one (may be used multiple times). ## CONFIGURATION Unless otherwise specified, eight NFS server threads are started and both UDP and TCP transports are supported. A server should run enough threads to handle the maximum level of concurrency from its clients. See [nfs.conf(5)](/nfs.conf/5.md) for a list of tunable parameters. ## NOTES The exports list displayed via [showmount(8)](/showmount/8.md) may contain additional information about the status of each export. This information is reported as entries in the export's group list. If an export is currently unavailable, the group list will begin with the entry "\" (or "\" if it is unavailable to some but not all clients exported to). If an export allows non-default security mechanisms, the group list will contain an entry indicating what security mechanisms are allowed. For example: "\". The mechanisms are listed in no particular order and may not be available to all clients. If an export is available to all clients, the group list is usually empty. But if additional status information is returned in the group list, then the list will also contain an explicit "(Everyone)" entry to indicate that the export is available to all clients. If **nfsd** does not have read access to an export, mount would fail with "Permission denied" and **checkexports** command would report the following error: ``` sandbox_check failed. nfsd has no read access to ``` This could be resolved by granting **nfsd** "Full Disk Access" under "Privacy" tab of the "Security & Privacy" preference in the "System Preferences" followed by restart of **nfsd** service. ## FILES - */etc/exports* The list of exported filesystems. - */var/run/nfsd.pid* The pid of the currently running nfsd. - */var/run/mountd.pid* The pid of the currently running mountd (provided for backwards compatibility with scripts that may HUP mountd to update exports). - */var/run/mountdtab* The current list of outstanding mounts served. - */var/run/mountdexptab* Information about exported file systems and directories (UUIDs, handles, ...). - */System/Library/LaunchDaemons/com.apple.nfsd.plist* The **nfsd** service's property list file for launchd(8). ## SEE ALSO [exports(5)](/exports/5.md), [nfs.conf(5)](/nfs.conf/5.md), [showmount(8)](/showmount/8.md), [nfsstat(1)](/nfsstat/1.md), [nfssvc(2)](/nfssvc/2.md), [portmap(8)](/portmap/8.md), [rpc.rquotad(8)](/rpc.rquotad/8.md), launchd(8) ## HISTORY The **nfsd** and **mountd** utilities first appeared in 4.4BSD. **mountd** functionality was merged into **nfsd** in Darwin 9.